Improvement in concrete pavements



CYRUS M, WARREN, OF BROOKLINE, MASSACHUSETTS.

IMPROVEMENT IN CONCRETE PAVEMENTS.

Specification forming part of Letters Patent No. 179,831, dated July 11, 1876; application filed J anuary 11, 1876.

To all whom it may concern:

Be it known that I, CYRUS MQWARREN, of

rosin and the tarry residuum or heavy oil of petroleum or candle-tar.

Concrete composed principally of coal-tar or coal-tar pitch and sand, broken stone, or

equivalent, has been used for a long time as a pavement, and the utilization of such concrete is very desirable, on account of its low cost. Pavements made't'rom such concrete, howevei, very soon deteriorate. The volatile matters, largely mixed with coal-tar or coal-tar pitch, evaporate by the influence of the atmosphere, and the concrete becomes brittle, and in a short time the pavement is full of cracks and holes.

This difficulty I have obviated by applying to a pavement composed of a concrete containing coal-tar or coal-tar pitch a protecting layer of native bitumen or asphaltum, or a compound made of native bitumen, or asphaltum, or rosin, and of the heavy oil or residuum of petroleum or candle-tar, to which may also be added sand, ashes, broken stones, or equivalent material;

In the preparation of this compound I have selected ingredients which are free, or nearly so, of volatile matter, and which at the same time can be obtained at a low cost.

My compound is prepared by fusing bitumen or rosin together with a suitable quantity of the heavy oil or residuum of petroleum or candle-tar. When cold my compound hardens, and itcan be easily put up in barrels for convenient transportation. When it is to be used the barrels are broken up, the compound is heated, and it can be readily spread on the concrete.

By applying this protecting layer to a concrete'pavement containing coal-tar or coal-tar pitch the following desirable objects are attained: first, increased durability without much additional cost second,inereased solidity when new,admitting of immediate-use without injury and without the liability to crack and crumble to dust when old or during the prevalence of cold weather; third, the continued utilization,

of coal-tar and coal-tar pitch as a paving material of a low cost, but under improved eondit1ons,wh1ch ett'ectually overcome the wellknown objections to its use as now employed.-

The protecting layer, being composed of materials-almost entirely free from volatile constituents, is not liable to deteriorate by the influence of the atmosphere, and it serve' s'to protect the foundation of inferior concrete against the deteriorating influence of the atmosphere.

A pavement-can thus be produced which is I equal in durability to a pavement composed day of January, 1876.

CYRUS M. WARREN. [L. s.] Witnesses:

W. HAUFF,

E. FJKASTENHUBER. 

